Animal marker

ABSTRACT

A system for implanting a solid marker in an animal is provided. The apparatus includes a hollow tube having an entrance and an exit opening. A support is provided for supporting a hollow tube. A plunger is slideably disposed between a first position and a second position within the support. The plunger cooperates with the support and the tube. The plunger engages the marker proximate to the entrance opening of the tube, and ejects the marker through the tube when the plunger is moved from a first position to a second position. The hollow tubes are stored within the support in at least two groups. A gate prevents a tube from the second group from being displaced before the tubes from the first group as depleted.

CROSS REFERENCE TO RELATED APPLICATION

This is a division of application Ser. No. 07/248,451 filed on Sept. 23,1988, now U.S. Pat. No. 5,002,548, which is a Continuation-In-Part ofU.S. application Ser. No. 06/919,152 filed Oct. 6, 1986 now U.S. Pat.No. 4,787,384.

BACKROUND OF THE INVENTION

This invention relates, in general to a system for implanting anidentification marker in an animal and, in particular, to a system forfacilitating implantation and retention of an identification marker intoa laboratory animal.

Heretofor, the marking of animals for tracking and testing purposes hasinvolved marking the animal externally, i.e. tatooing, branding ortagging. These external markers are difficult to read when identifyingthe animal and are extremely limited in the amount of information aboutthe animal that can be carried by the external marker.

In order to overcome the disadvantages noted above with externalmarkers, a system has been proposed whereby markers carrying informationthat can be read by an external detector can be implanted in a testanimal. However, such a system requires an instrument that permits amarker to be delivered into the animal without difficulty and whereinthe marker will remain securely embedded in the lab animal for aconsiderable length of time.

SUMMARY OF THE INVENTION

Generally speaking, in accordance with the invention, an improvedapparatus for implanting a marker into an animal is provided. Theapparatus includes a hollow tube having an opening at each end. Anentrance end of the hollow tube is supported within a housing. An exitend of the tube is sharp to allow subcutaneous penetration of the tubeunderneath the skin of a laboratory animal. A plunger is slideablymounted within the housing. The plunger is adapted to displace themarker from a first position in the tube out of the exit end of thetube. The tubes are stored within the instrument itself in a series ofrows. A gate clip prevents each successive row of tubes from intermixingwith the previous row of tubes.

In an exemplary embodiment, an electronic transponder containinginformation about the animal, such as identification numbers, is placedin the marker. When the tube is inserted below the skin of the animaland the plunger is displaced, the marker containing the electronictransponder is forced through the tube, lodging it underneath the skinof the animal.

An object of this invention is to provide an improved apparatus forimplanting markers in laboratory animals.

A further object of this invention is to provide an implanting systemfor facilitating identification of laboratory animals.

Still a further object of this invention is to provide an easy to useimplanting instrument for implanting a marker into a laboratory animal.

Yet a further object of the invention is to provide an implanting systemfor implanting a marker subcutaneously in the animal so that the markerwill be retained within the animal.

Yet a further object of the invention is to provide an implanting systemfor implanting a marker subcutaneously in the animal so that the markerwill be retained within the animal.

The invention accordingly comprises features of construction,combination of elements and arrangement of parts which will beexemplified in the construction hereinaftert set forth and the scope ofthe invention will be indicated in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

For a fuller understanding of the invention, reference is had to thefollowing description taken in connection with the accompanyingdrawings, in which:

FIG. 1 is a perspective view of an animal marker implanting instrumentconstructed in accordance with a preferred embodiment of the instantinvention;

FIG. 2 is a partial sectional view taken along line 2--2 of FIG. 1;

FIG. 2A is a sectional view taken along lines 2A--2A of FIG. 2;

FIG. 3 is a partial sectional view taken along line 2--2 of FIG. 1;

FIG. 4 is a partial sectional view taken along line 4--4 of FIG. 3;

FIG. 5 is a partial sectional view taken along line 5--5 of FIG. 3;

FIG. 6 is a partial sectional view taken along line 2--2 of FIG. 1, whenthe needle assembly is inserted therein;

FIG. 7 is a sectional view taken along line 7--7 of FIG. 6;

FIG. 8 is a perspective view of the implanting instrument illustrated inFIG. 1 in use;

FIG. 9 is a plan view of the implanting instrument illustrated in FIG. 1in use;

FIG. 10 is a sectional view taken along line 10--10 of FIG 9;

FIG. 11 is an enlarged partial sectional view of the implanterinstrument illustrated in FIG. 10;

FIG. 12 is a sectional view of the implanting instrument taken alongline 12--12 of FIG. 11;

FIG. 13 is a perspective view of the needle assembly;

FIG. 14 is a sectional view of the marker depicted in FIG. 11;

FIG. 15 is a sectional view taken along line 15--15 of FIG. 13; and

FIG. 16 is a perspective view of a cylinder to be used as part of theinstant invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference is initially made to FIGS. 1 through 15, wherein an animalmarking system including an implanting instrument, generally indicatedat 10 (FIG. 1), a needle assembly, generally indicated as 19 (FIG. 13)and an animal marker, generally indicated as 30 (FIGS. 11, 12 and 14) isdepicted. As is explained in greater detail below, the cooperation ofthe needle assembly, marker and implanting instrument permits the facileimplantation of a marker into a laboratory animal and the retention ofthe marker within the animal during long periods of laboratorymonitoring and testing.

Reference is now particularly made to FIGS. 1 through 5, whereininstrument 10 is illustrated in detail. Instrument 10 defines twoopposed half walls 27 which are molded in mirror image and securedtogether to define a unitary housing in the shape of a handle 31. Eachopposed wall 27 is defined by a substantially parallelogram shapedconfiguration including lengthwise mating walls 27a and lateral matingwalls 27b and 27c. As is explained in greater detail below, mating walls27a are inclined with respect to lateral mating walls 27b to definehandle 31 and to facilitate storage therein of a plurality of needleassemblies. A cap 34 is slideably mounted to the housing defined inopposed wall 27. In an exemplary embodiment, at least one of the opposedwalls 27 can be transparent or translucent to allow the user to view theneedle assemblies 19 disposed within the handle.

Cap 34 is normally disposed in a closed position, and can be displacedin the direction A (FIG. 2) from a closed position (solid lines in FIG.2) to an open position (phantom lines in FIG. 2). As is illustrated inFIG. 7, cap 34 includes side walls 34a and gripping walls 34b which aredisposed in elongated slots 27' formed in opposed walls 27. Cap 34includes ribs 35 on the side for permitting the cap to be easily grippedand can be displaced between an open and closed position. An arrow 37 orother indicia can be imprinted on cap 34 to indicate the properdirections for sliding.

Opposed lateral walls 27b are covered by cap 34 when cap 34 is in aclosed position. Opposed lateral walls 27b are configured to defineopposed recessed walls 38a and an open chamber, generally indicated at38, for receiving a needle assembly and for permitting each needleassembly to be dispensed through the opening from the interior of thehousing when cap 34 is displaced to an open position. Opposed lateralwalls 27b are further configured to define a channel 39 which orientsthe needle assembly when it is positioned in chamber 38.

Referring particularly to FIGS. 10 through 15, needle assembly 19 isformed from a stainless steel hollow tube 20 having an exit opening 21and an entrance opening 23. Exit opening 21 is formed in the shape of aninclined edge 22 which forms a sharp point for permitting the tube toeasily penetrate an animal's skin. The side of tube 20 having entranceopening 23 is molded in a plug 24. Plug 24 includes a sleeve 25integrally formed therewith and projecting about tube 20 to extend alonga portion of the tube's length. Plug 24 includes arcuate end walls 24afor facilitating the positioning of the plugs in chamber 38 in a mannerthat will be discussed in detail below. As is particularly illustratedin FIG. 15, marker 30 is positioned in tube 20 near the exit opening 21thereof. A drive pin 16 is used to position the marker within the tube.Drive pin 16 includes a sealing disc 17 that is integrally moldedtherewith. Sealing disc 17 has an outside diameter that is sufficient tointerference fit with the inside diameter of the tube 20 and preventdisplacement of the drive pin during normal storage and handling of theneedle assembly. Drive pin 16 aids in positioning the marker in thetube. However, it has been found necessary to facilitate positioning ofthe marker in tube 20 particularly when the marker is a glass capsule inorder to prevent the marker from slipping out of the exit opening of thetube.

Reference is now made to FIGS. 11 and 12 wherein a projection 29integral with sleeve 25 extends through opening 28 in order to preventthe marker from slipping or moving in the tube prior to the discharge ofsame into the animal. This projection can be easily formed duringassembly of the hollow tube within plug 24 by molding the plug about thetube and permitting the resin used to form the tube to enter aperture28. Projection 29 is intended to frictionally engage marker 30 when themarker is positioned within tube 20 to prevent the marker from slidingin the tube. Projection 29 will hold the marker in place until a forcesufficient to push marker 30 through tube 20 is applied to a plungerand, in turn, to the marker.

In an exemplary embodiment, tube 20 is stainless steel. However, tube 20may be made from other rigid FDA approved materials, such as Ultem®,manufactured by General Electric. Also, as aforenoted, sleeve 25 andplug 24 can be integrally formed by injection molding a plastic resinabout the entrance opening of tube 20. Also, the sleeve and plug may beformed of rigid materials other than plastic.

Needle assembly 19 is easily positioned in chamber 38 when cap 34 isdisplaced into an open position. Moreover, needle assembly 19 is tightlysecured within chamber 38 by returning cap 34 to a closed position. Thisprevents any wobbling of the needle assembly 19 during use.

Plunger 18 includes a rod 41 and a knurled surface 43 integrally formedat one end of rod 41. Plunger 18 is slideably mounted within elongatedchannel 39 formed by lateral walls 27b formed in the top of the housing.Knurled surface 43 projects through elongated opening 44 in cap 34 andpermits the plunger to be displaced between a start position and animplanting position. Channel 39 is coaxially aligned with the entranceopening 23 of tube 20 of the needle assembly 19 and alignment channel 49to form a continuous pathway for rod 41 when needle assembly 19 isretained in chamber 38. Knurled surface 43 extends through elongatedopening 44 (FIG. 9) in cap 34, allowing displacement of the plunger 18by pushing knurled surface 43 from a start position to an implantingposition. Plunger 18 also includes seats 18a projecting therefrom whichrests against stops 27e formed by opposed half walls 27. Stops 27e andseats 18a cooperate to normally maintain the plunger at the startposition depicted in FIG. 6.

The distance of the placement of the marker in the tube from the exitopening and the length of elongated opening 44 have relative lengthswith respect to each other. When cap 34 is displaced in the direction Ainto an open position, it will capture knurled surface 43 if it is notalready in a start position and displace the plunger to a start positionso that rod 41 is entirely displaced outside of the entrance opening 23of the needle assembly 19. Furthermore, the distance of the placement ofthe marker from the exit opening determines the distance through whichthe rod will be displaced and, hence, the preferred distance ofelongaged opening 44. Moreover, this distance further assumes that rod41 is entirely displaced without the entrance opening of the tube whenplunger 18 is in a start position. This permits placement of needleassembly 19 in chamber 38.

When cap 34 is returned to a closed position, stop 27e helps maintainplunger 18 at its start position so that the plunger is notunintentionally pushed forward. If slideable cap 34 is not pushedentirely into a closed position, knurled surface 43 is prevented frombeing pushed forward sufficiently to cause plunger 18 to eject themarker 28 from the needle assembly 19. This configuration prevents useof the instrument unless the needle assembly 19 is fully secured withinchamber 38 and is securely captured by cap 34 being displaced into aclosed position. Also, since knurled surface 43 of the plunger 18 comesin contact with the cap at the limits of elongated opening 44, theplunger 18 is automatically positioned by manipulating the cap.

Reference is now also made to FIG. 8, wherein operation of the instantinvention is depicted. In an exemplary embodiment, marker 30 is storedwithin tube 20 and is retained therein by a projection 25. Cap 34 isthen slid into an open position. Needle assembly 19 is then pivotablydisplaced into chamber 38. Cap 34 is then displaced forward into aclosed position supporting and anchoring needle assembly 19 securely inplace within chamber 38 and channel 49.

Next, a test animal, such as a mouse 46, must be stabilized. Asillustrated in FIG. 8, a mouse can be picked up in the user's one handand the implanting instrument held in the user's other hand. However, asis illustrated in FIG. 16, in an exemplary embodiment, a cylinder 80that is open at both ends can be utilized to render the head of themouse immobile. By inserting the mouse's head in a cylinder the mousecannot turn its head and bite the user's hand or otherwise interferewith the procedure. Furthermore, once the mouse's head is immobilized inthe cylinder it permits the hand of the user to be used to stretch theanimal's skin and thereby facilitate manipulation of the mouse duringsubcutaneous implantation. Accordingly, the implanter systems of theinstant invention contemplates the use of different sized tubes toaccommodate the distinct differences in the size of the laboratoryanimals. Once the animal is immobilized, the user is prepared to inserttube 20 into the laboratory animal.

Exit end 21 of tube 20 is inserted subcutaneously into mouse 46 untilthe animal's skin 48 reaches the edge of sleeve 25. This automaticallyplaces marker 30 at the desired position beneath the skin. Knurledsurface 43 of the plunger 18 is then pushed forward, preferably with theuser's thumb 50, with enough force such that plunger 18 engages drivepin 16. Knurled surface 43 is displaced until knurled surface 43 isdisposed into an implanting position so that rod 43 comes in contactwith the end of opening 44 in cap 34. At this point, plunger rod 41 ofplunger 18 has engaged drive pin 16 and extends far enough within tube20 to have forced drive pin 16 to eject marker 30 from tube 20underneath the animal's skin. Next, the implanting apparatus is removedfrom animal skin 48, cap 34 is pulled back and needle assembly 19 isremoved and discarded. The process may then be repeated for anotheranimal.

In an exemplary embodiment, marker 30 is a glass capsule having thereinan electronic transponder 35 containing identification information aboutthe animal. This is used by way of example only. This process isadaptable to the implantation of any type of marker. Marker 30 is formedby embedding an electronic transponder 35 in a glass capsule. By usingan electronic transponder, the amount of storable information is greatlyincreased, especially when transponder information can be directlylinked to computer systems containing further information and processingsoftware. Because the capsule is glass, it tends to slide easily instainless tube 20. It is for this reason that projection 29 is used tointerference fit the capsule in the tube and prevent same from movingwithin the tube during storage and handling of the needle assembly.

Each needle assembly 19 is sealed within a sanitary sleeve 33 which canbe easily removed when the needle assembly is displaced into chamber 38for use in the manner described above. Moreover, after sanitary sleeve33 is used to cover the exit opening of the tube, a sterilant gas can beinjected into a chamber defined by tube 20, drive pin 16 and sealingdisc 17 and the sleeve 33. By introducing a sterliant gas, the markercan be sterilized and remain sterilized until the needle assembly isready for use. Furthermore, as is illustrated particularly in FIGS. 2through 5 and 13, the opposed side walls 27 of the housing and the plug24 of each needle assembly are configured in a manner discussed below topermit each needle assembly to be stored in the handle and removedtherefrom for easy use.

Specifically, a pair of opposed ramps 45 are formed in each wall 27.Ramps 45 are formed in mirror image on each wall so that they aredisposed in registry with each other when walls 27 are brought togetherto form the housing defining handle 31. Furthermore, each ramp isdisposed in parallel with lateral wall 37c and at an angle with respectto the lengthwise extent of the handle. Ramps 45 are spread a sufficientdistance apart to permit two rows of needle assemblies to be stored inhandle 31.

The plug of each needle assembly 19 includes positioning grooves 26found in opposed surfaces, the grooves being disposed on an angle withrespect to the lengthwise extent of the plug and diagonally opposed witheach other to facilitate placement of each needle assembly 19 in thehousing during assembly of the product. As is illustrated with someparticularity in FIGS. 3 through 5, each needle assembly can bepositioned within handle by racking the plug onto a first ramp 45 sothat the ramp is positioned within the positioning groove 26. The groove26 and ramp 45 prevent any substantial lengthwise displacement of eachneedle assembly during storage and use of the instrument. The opposingramp assists in positioning the plug by pressing against the plug. Eachramp 45 includes a positioning ramp 45a that is parallel with thelengthwise side walls 27a of handle 31. Positioning ramp 45a does notprotrude as far as ramp 45 and is provided to assist in preventing theplug from sliding laterally and to further assist in guiding the needleassembly through the opening in chamber 38 when a needle assembly is tobe removed from the handle.

In an exemplary embodiment, ten needle assemblies are stored on eachramp 45. As noted above, wall 27a and ramp 45a facilitate delivery ofeach needle assembly to the operator.

As is illustrated in FIG. 2, the opening in chamber 38 is sufficientlylarge to permit the needle assembly to be removed therethrough.Accordingly, when a needle assembly is needed, cap 34 is displaced froma closed position to an open position. By manipulating the orientationof the housing, a needle assembly positioned closest to chamber 38 willthen slide out of the housing through opening 38. As aforenoted, suchmanipulation can be facilitated by forming one of the opposed walls 27forming handle 31 out of a transparent or translucent material. It isthen a simple matter to position plug 24 of the needle assembly inchamber 38, slide cap 34 to a closed position and remove the sanitarysleeve 33, so that the user is ready to begin implantation of the markerin the manner discussed above.

Reference is now made to FIG. 14, wherein a marker 30 is formed of asmooth material 81, such as glass. As aforenoted, the use of a glassmarker can be problematical. First, when the needle assembly does notinclude a projection 29, marker 30 is not secured in the tube and,hence, the marker may slide out of the tube of the needle assemlby.Also, it has been observed that when a glass encapsulated transponder 35is implanted in a laboratory animal, migration of the transponder out ofthe wound of the animal can occur. Accordingly, in a preferredembodiment, one-half of marker 30 is coated with a layer 83 having ahigh coefficient of friction. For example, Silastic®, manufactured byDow Corning, has been successfully used. Also, polypropylene has beenused as a coating. By utilizing a layer coating marker 30, projection 29can be eliminated, thereby allowing for a thinner tube 20 having agreater inner diameter than the embodiments containing projection 29.

The instant invention further contemplates a method of forming layer 83about a glass marker. Specifically, markers are partially inserted intoa mold cavity. Thereaftrer, a polypropylene resin is injected into themold cavities and cured about the marker to define a suitablenon-slippery surface.

In a further embodiment, the outer surface of glass of marker 30 can beetched. Although etching of the outer glass coating prevents migrationin the animal, projection 29 is still needed to hold marker 30 in placein the tube 20. However, etching has been found to weaken the marker andalthough experimentally viable, does not appear to offer the sameefficiency as the use of a coating on the glass capsule.

It will thus be seen that the objects set forth above, and those madeapparent from the preceding description, are efficiently attained and,since certain changes may be made in the above construction withoutdeparting from the spirit and scope of the invention, it is intendedthat all matter contained in the above description or shown in theaccompanying drawings shall be interpreted as illustrative and not in alimiting sense.

It is also to be understood that the following claims are intended tocap all of the generic and specific features of the invention hereindescribed, and all statements of the scope of the invention which, as amatter of language, might be said to fall therebetween.

What is claimed is:
 1. A marker adapted to be injected subcutaneouslyinto a laboratory animal by an implanting apparatus comprising a glasscapsule having therein an electronic transponder, and anti-migrationmeans covering at least a portion of said capsule, said anti-migrationmeans preventing migration of the marker from said laboratory animal. 2.A marker as claimed in claim 1, wherein said anti-migration meansincludes a layer coating at least a portion of the surface of thecapsule.